This dissertation investigates Marx's thinking with a view to ascertaining normative foundations for a system of ethics in capitalist society. It presupposes as essential to the functioning of an ethics or morality: a conception of the good life for individuals living together in society; and a means of embodying this conception in an analysis of moral agency. The investigation establishes Marx's understanding of the status of ethics or morality in capitalist society in general by considering his view of the status of each of these two elements, independently and in conjunction with one another. The principal part of the dissertation is introduced by critical evaluation of three contemporary Marxist philosophers' views concerning Marx's understanding of the two foundations of an ethics or morality: Althusser, Ollman, and Meszaros. It is argued in the principal part of the dissertation that Marx did believe a conception of the good life relevant to capitalist society, that there is a basis for moral agency in capitalist society, and thus that ethics is viable in that society on his view.